New T56 Mangum - 2nd Gear Grind

[AU Doc]

I have a new T56 Magnum with maybe a couple hundred miles on it. This is my first T56, and most of my previous experience has been with mid-90s T5s in Mustangs.

This transmission has a noticeable crunch going into 2nd gear, and at times even a little grinding or clunking if I shift too slow or at just the right speed/rpm. If I shift fast(er) or jamb it into gear it seems to be perfectly happy. Easy/slow shifting seems to be the only time I have any issues, and I've even had it pop out of gear when shifting slow because it felt like it was in gear. All the T5s I've driven are much smoother, and I certainly can't feel the slider clicking onto the blocker and then onto the gear teeth like I do with this T56.

The clutch seems to disengage pretty close to the top of the travel. I've put the car up on jack stands and rev'ed the engine with it in gear and the clutch depressed and the tires don't spin. So it doesn't appear that the clutch is dragging. It doesn't seem to be related to heat. I also indexed the bell for concentricity and parallel when I installed the transmission. It was on the upper end of the tolerance, but still within range.

I've read tons of threads where the "notchy" feel of the T56 is discussed, but I'm not sure if that is the same thing as what I'm feeling.

What say you? Normal? Broken? Drive it like I stole it and be happy?

[randy]

Bleed the system again. It will get better the more you drive it

[AU Doc]

Thanks!

Just out of curiosity, are you suggesting bleeding the clutch because the clutch may be dragging? Is that even though the wheels don't spin when revving the engine with the clutch depressed?

[randy]

I just felt that driving it for awhile might have released a few more bubbles. I relaxed my oil as well after 500 miles to some redline d4

[ADY]

I have over 3k miles on my t56 and have the same; seems to happen when you shift slow in to 2nd but not when partially engage and then fully shift in to gear, or slam it through the gears.

[AU Doc]

partially engage and then fully shift in to gear,.

This has caused me to grind second on a few occassions. Being a new drivetrain swap, the first few weeks I was going really easy on the car, and shifting very easily (it’s strangely difficult to drive a car easily, but slam it into each gear). Driving like that meant I would gently shift into second, but not get that extra clunk, or notch, or crunch, or however it’s best described before letting out on the clutch. Yeah, it makes a very angry noise when you do that.

I’m fairly certain what’s happening is the slider is engaging the blocker (first notch), and then there’s a second notch where the slider engages the gear. The problem is sometimes you feel both notches, but sometimes you don’t.

[Oleyellar]

https://www.facebook.com/TheWebmThread/videos/2040689582886541/?t=21
You should learn to shift like this guy.

[AU Doc]

You should learn to shift like this guy.

LOL!!! I see I've been doing it wrong all these years :)

[rustomatic]

Wow, this really blows--I'd return the thing. One test would be to shift without the clutch, just like you would with a big-rig ten-speed. Rev to normal shift speed, then apply pressure to the shifter (outward); it will pop out of gear when you let off the gas. Quickly place it against the next gate before RPMs drop too far; timed correctly, you'll go into the next gear like butter. (Tap gas lightly to get revs back up if they fall too far.) If it goes into the next gear, it should not grind (it will of course grind if you miss the gear). This does not sound like a clutch problem, though. It's cementing my motivation for going to a Nissan CD009 when I have to suck it up and go back to a manual . . .

[AU Doc]

I've been thinking about what could be the cause of this. The only thing I can come up with is the blocker doesn't seem to clear the oil away from the cone face as well as it should. With light shift pressure I'm guessing there is still a fluid pad/wedge between the blocker and the cone, which is allowing the gear to continue to rotate. That would cause the occasional grind/crunch going into gear.

With higher shift pressure, it forces the fluid out more aggressively, and allows the blocker to fully engage the gear. I'm also guessing that once the blocker and cone faces wear in a little, you pick up some contact surface by wearing down the high spots on the friction material, which improves the situation.

Different fluids, particularly synthetics, likely have different cling and shear properties. That would also affect how pronounced this is, as a better flowing fluid would clear off of the cone better, and allow the blocker to engage the gear. That would explain why some people claim changing fluids fixed their issue, or made their transmission shift better.

This is all speculation on my part, but it seems plausible based on my limited knowledge of how it works. Unfortunately, it doesn't do anything to fix the problem.

[TheJDMan]

It's called 2nd gear nibble, at least that's what the tech at AP told me when I called and ask about it. This is not uncommon in a new T56 Magnum. My T56 did the same thing when new and I asked the same question. I was told it gets better as the transmission breaks in. It does. I have around 10,000 miles now on my new Magnum and the shifting is dramatically improved. I still get a very slight 2nd gear nibble when I first start driving each day but once the transmission comes up to temp the nibble goes away. The only thing I would recommend is that you service the transmission with new ATF somewhere between 2000 to 3000 miles.